There are several parallels between the careers of British directors Pete Walker and Norman J Warren. Both started out making 'adult films' before switching to horror. Both moved away from the traditional Gothic favoured by Hammer to much more contemporary genre pieces, several written by ex-Monthly Film Bulletin deputy editor David McGillivray. And both men's careers foundered by the 1980s, when European exploitation 'out-gored' domestic productions. However, Walker's films eschewed Warren's supernatural themes, focusing instead on the evil in people, making them much more akin to American independent horror films of the early 1970s.

The son of musical comedy performer Syd Walker, Pete himself started as a stand-up in a Soho strip club. After acting in low-budget British programme-fillers, he set up his own company in the early 1960s, producing 8mm glamour films. Using the money from this highly lucrative enterprise, he graduated to 35mm feature production, making films like Strip Poker (1968) and Cool it Carol! (1970), which marked Robin Askwith's soft porn debut. Under his own 'Peter Walker (Heritage)' brand, he even experimented with 3-D technology, in The Four Dimensions of Greta and The Flesh and Blood Show (both 1972).

Finding the 'adult film' genre repetitive, he moved to horror, although he preferred the term 'terror films' as he didn't feel any particular affinity for the genre, despite being aware of its potential. Exploring the themes of abuse of authority and the widening generation gap that he perceived in society, Walker's best films were scathing indictments of British institutions: in House of Whipcord (1973), a couple running a corrective prison torture the inmates, Frightmare (1974) saw a couple released from a mental institution luring people to their farm and murdering them, while The House of Mortal Sin (1975) depicted a Catholic priest terrorising a young girl). While most critics savaged the films, the Monthly Film Bulletin found more in them than just exploitation, comparing House of Whipcord to Michael Powell's psychological thriller Peeping Tom (1960).

Despite varying reviews, the films were hugely successful at the box office but Walker's career was waning by the late 1970s. His only non-independent film was also his last: the Golan-Globus production House of the Long Shadows (1982), an adaptation of the classic Seven Keys to Baldpate, was a fitting final production, a nostalgia piece starring horror veterans Peter Cushing, Christopher Lee and Vincent Price. After abandoning film-making, Walker went into property development.